Liquid film falling behaviour on horizontal circular cylinder

Abstract

The flow pattern behaviour of falling liquid film over three horizontal cylinders was evaluated. These flows can take three forms: discrete droplets, individual jets, and continuous sheet, and special attention is paid to the effects of the physical properties and geometrical parameters of the first two forms (droplets and jets) because these forms are more important in heat-transfer behaviour and less research has been published for these forms. The flow modes and experimental results were successfully compared with previous experimental literatures, and also the effects of liquid flow rate, tube diameter, and tube spacing on departure site spacing, in both drop and jet modes, were evaluated in the low Galileo number and high viscosity fluid (cooking oil), to help developing criteria for determining falling film modes and their transitions, and to understand the heat transfer characteristics associated with each mode.